In 1162, Alexander was forced into exile in France by Emperor Frederick I. In his long struggle with the emperor, the pope was aided by the Lombard League, which named the town of Alessandria for him. In 1174, he received the penance of King Henry II of England for the murder of SaintThomas Becket. Following the Battle of Legnano in 1176, Frederick was finally forced to submit to papal authority.

Alexander convened the Third Lateran Council. He issued many decretals, established the procedure for canonizingsaints, inaugurated the two-thirds rule for papal elections, protected universities, and was one of the most distinguished champions of ecclesiastical independence in the Middle Ages.